With the advent of high speed copiers, such as xerographic reproduction machines, automatic document handlers have become a necessity to rapidly place and remove documents from the platen of the copy machine to enable the machine to produce copies at its full potential. The document handler must first separate the document to be copied from others awaiting copying. Following this, the document must be brought into position on the machine platen and located in a certain position to assure the making of a complete and visably acceptable copy. After the document has been copied, it is returned to the document supply tray. To maximize copy output, the documents must be handled rapidly and with great care to prevent damage to mutilation thereto since the documents may be one of a kind and/or irreplaceable. One of the problems that has heretofore been encountered is in assuring that the documents returned to the document tray have properly settled therein and are clear of the document return path so that subsequent documents do not collide with previously returned documents causing damage thereto or jamming the automatic document handler. This problem has been addressed in a number of ways. For example, in U.S. Pat. No. 3,790,158, granted Feb. 5, 1974 to James E. Summers et al and assigned to the assignee of the present application, a fan in the return tray area is employed to discharge a low pressure stream of air downwardly onto the documents therebelow in the tray assembly to move the returned documents clear of the document return path into the tray. As a further safeguard, a sheet sensing device is also employed to prevent return of subsequent documents if for any reason a document is not cleared from the return path by the low pressure air stream. While this system has proved quite satisfactory, in the event that the sensor does disable the document feeder due to the presence of a returned document in the document return path, the operator must check the document tray and correct the situation before the machine is allowed to continue operation and valuable machine time may be lost.